Interrogation of Carboxy-Terminus Localized GJA1 Variants Associated with Erythrokeratodermia Variabilis et Progressiva

Although inherited GJA1 (encoding Cx43) gene mutations most often lead to oculodentodigital dysplasia and related disorders, four variants have been linked to erythrokeratodermia variabilis et progressiva (EKVP), a skin disorder characterized by erythematous and hyperkeratotic lesions. While two autosomal-dominant EKVP-linked GJA1 mutations have been shown to lead to augmented hemichannels, the consequence(s) of keratinocytes harboring a de novo P283L variant alone or in combination with a de novo T290N variant remain unknown. Interestingly, these variants reside within or adjacent to a carboxy terminus polypeptide motif that has been shown to be important in regulating the internalization and degradation of Cx43. Cx43-rich rat epidermal keratinocytes (REKs) or Cx43-ablated REKs engineered to express fluorescent protein-tagged P283L and/or T290N variants formed prototypical gap junctions at cell–cell interfaces similar to wildtype Cx43. Dye coupling and dye uptake studies further revealed that each variant or a combination of both variants formed functional gap junction channels, with no evidence of augmented hemichannel function or induction of cell death. Tracking the fate of EKVP-associated variants in the presence of the protein secretion blocker brefeldin A, or an inhibitor of protein synthesis cycloheximide, revealed that P283L or the combination of P283L and T290N variants either significantly extended Cx43 residency on the cell surface of keratinocytes or delayed its degradation. However, caution is needed in concluding that this modest change in the Cx43 life cycle is sufficient to cause EKVP, or whether an additional underlying mechanism or another unidentified gene mutation is contributing to the pathogenesis found in patients. This question will be resolved if further patients are identified where whole exome sequencing reveals a Cx43 P283L variant alone or, in combination with a T290N variant, co-segregates with EKVP across several family generations.     

Preparation of BaTi4O9 from Oxalates

A barium titanate precursor with a barium:titanium ratio of 1:4 was prepared by controlled coprecipitation of mixed barium and titanium species with an ammonium oxalate aqueous solution at pH 7. The results of thermal analysis and IR measurement show that the obtained precursor is a mixture of BaC₂O₄·0.5H₂O and TiO(OH)₂·1.5H₂O in a molar ratio of 1:4. Crystallized BaTi₄O₉ was obtained by the thermal decomposition of a precipitate precursor at 1300°C for 2 h in air. The dimensions of the powder calcined at 1000°C are between 100 and 300 nm. The grain dimensions of the sintered sample for 2 h at 1300°C are of the order of 10 to 30 μm. Dielectric properties of disk-shaped sintered specimens in the microwave frequency region were measured using the TE₀₁₁ mode. Excellent microwave characteristics for BaTi₄O₉—ɛ= 38 ± 0.5, Q = 3800–4000 at 6–7 GHz and τ _f = 11 ± 0.7 ppm/°C—were found.     

Synthesis and adsorption properties of nanocrystalline ferrites for kinetic modeling development

Nanocrystalline ferrites are known to be used in different applications, including industrial wastewater management. For environmental water issues, one of the most widely applied techniques is the adsorption of pollutants. The adsorption capacity of Congo red (CR) dye on different MFe₂O₄ (M = Co²⁺, Mg²⁺, Mn²⁺, Ni²⁺, and Zn²⁺) ferrites, synthesized by coprecipitation method, was determined. Specific isotherms and kinetic models were used to characterize the adsorption process. Interesting results were obtained for MgFe₂O₄ with adsorption capacity ranging from 39% up to 70% dependent on the initial dye concentration. Furthermore, an artificial intelligence model based on neural network was developed in order to model the adsorption rates followed by the generation of 3D adsorption rate models for each type of synthesized ferrite. These models were obtained in order to provide information about the particle-dye system`s kinetics at various initial CR concentration. Specific techniques were used to characterize the functionalized magnetic particles.     

Discovering novel memory cell designs for sentiment analysis on tweets

Designing a Recurrent Neural Network to extract sentiment from tweets is a very hard task. When using memory cells in their design, the task becomes even harder due to the large number of design alternatives and the costly process of finding a performant design. In this paper we propose an original evolutionary algorithm to address the hard challenge of discovering novel Recurrent Neural Network memory cell designs for sentiment analysis on tweets. We used three different tasks to discover and evaluate the designs. We conducted experiments and the results show that the best obtained designs surpass the baselines—which are the most popular cells, LSTM and GRU. During the discovery process we evaluated roughly 17,000 cell designs. The selected winning candidate outperformed the others for the overall sentiment analysis problem, hence showing generality. We made the winner selection by using the cumulated accuracies on all three considered tasks.

     

纳米纤维素基柔性导电薄膜的构筑及其在柔性电子器件中的应用研究进展

纳米纤维素（NC）因具有高比表面积、优异的力学性能、出色的热稳定性和可生物降解性,是柔性储能设备电极材料的理想候选者。在柔性电子器件的应用中,通常将NC与导电材料结合以提高其导电性。本文从NC的结构特点出发,综述了NC基导电薄膜的形成及其在柔性电子器件的应用,总结分析了NC基导电薄膜在实际应用中存在的问题和挑战,并对其未来的研究方向进行展望。     

Comparative Assessment of PV Plant Performance Models Considering Climate Effects

The climate conditions can affect the accuracy of photovoltaic (PV) system performance models that can be used for monitoring and diagnostic purposes. In this paper, an improved energetic physical model has been considered to estimate the power production of PV systems. Specifically, in this model, special attention has been devoted to the modeling of optical losses (IAM losses) and to the inverter efficiency under low-power conditions.

A comparative analysis of the proposed model applied to two PV plants installed respectively in the north of Denmark (Aalborg) and in the south of Italy (Agrigento) has been performed. The different ambient, operating and installation conditions allow to understand how these factors impact the precision and effectiveness of such model. The experimental results show that the proposed model allows us to have a good estimation of AC power in terms of Relative Mean Bias Error, normalized Root-Mean-Square Error, and the Correlation Coefficient. Further in order to have the possibility to analyze and compare the performance of the studied PV plants with others, the efficiency of the systems has been estimated by both Performance Ratio and Corrected Performance Ratio.     

Engineering preliminaries to obtain reproducible mixtures of atelocollagen and polysaccharides

The critical stage in producing blends of biomacromolecules consists in the mixing of component solutions to generate homogenous diluted colloidal systems. Simple experimental investigations allow the establishment of the design rules of recipes and the procedures for preparing homogenous and compositionally reproducible mixtures. Starting from purified solutions of atelocollagen, hyaluronan and native gellan, having as low as possible inorganic salts content, initial binary and ternary mixtures can be prepared up to a total dry matter content of 0.150 g/dL, in no co-precipitating conditions. Two pH manipulation ways are feasible for homogenous mixing: (i) unbuffered prior correction at pH 5.5, and (ii) “rigid” buffering at pH 9.0, using organic species. Atelocollagen including co-precipitates can be obtained in the presence of one or both polysaccharides, preferably in pH domains far from the isoelectric point of scleroprotein. A critical behavior has been observed in mixtures containing gellan, due to its macromolecular dissimilarities compared with atelocollagen. In optimal binary mixtures, the coordinates of threshold points on the phase diagrams are 0.028% w/w atelocollagen/0.025% w/w hyaluronan, and 0.022% w/w atelocollagen/0.020% w/w gellan. Uni- or bi-phasic ternary systems having equilibrated ratios of co-precipitated components can be prepared starting from initial mixtures containing up to 0.032 g/dL atelocollagen, associated with, for example, 0.040 g/dL hyaluronan and 0.008 g/dL gellan, following the first pH manipulation way.     

Phthalimide‐N‐oxyl (PINO) Radical,a Powerful Catalytic Agent: Its Generation and Versatility Towards Various Organic Substrates

The last two decades represents a “start line” for the worldwide chemists, to develop new oxidizing methods, to replace the “old‐fashioned” ones, which are expensive, pollute the environment, and proceed in harsh conditions. One of the best candidates to satisfy the present global needs is N‐hydroxyphthalimide (NHPI), which can be used as a catalytic reagent successfully in a wide range of organic transformations. In this article, a review of the most frequently used methods to transform the NHPI into its nitroxyl radical correspondent, and the use of this powerful catalytic agent into various organic transformations, are presented.